Phantom Powered Tube Mics

This idea seems kind of abandoned. Raytheon tube is cheap, and some documentation is available.

There is this Naiant MSH-4 mic:
https://naiant.com/microphone-design/

And Audio Technica patent files:
https://patents.google.com/patent/US20050254671?oq=akino+microphone+0254671

I don't know if it's legaly ok to explore further this patent, but it would be great to be able to make mics based on it. The values of components are absent obviously in the schem.

AT is great as it uses less current, but needs a transformer.

Maybe make a version with regular LDC capsule.

check the yahoo microphone group
look for zapandspark circuits

There was a very good thread at this forum years ago for a phantom powered tube DI change the input to connect to a capsule and you will have a tube phantom powered microphone.

An issue with some phantom powered tube microphones is the needed DC to DC converter for the heater and maybe the B+. Noise, interference, FCC etc.

Edit
https://groupdiy.com/index.php?topic=63496.msg804726#msg804726

https://groupdiy.com/index.php?topic=1195.0

Awesome, thanks!

Wow, amazing project. Exactly what i was thinking, it's Audio Technica AT3060 without transformer. Killer!

Anyone ever made a pcb layout?

Ha! I wanted even to make a kit with use of AT charging pumps idea
At the time i had problem to found local LM2665, only one shop had it but pretty expensive. Now i found it pretty cheap.
Maybe i will back to this project in september, we will see

I think people are not aware of this concept, and most think of these as starved plate designs.

Naiant version is great for live stage tube mic. This would be the first of it's kind i believe. Cant wait to try it out.

You shouldn't abandon this idea, it seems awesome.

I guess Russian 1j24B should work here. Any other options?

I was also thinking of using 1j24B, but still not sure how to do it...